Problem: Last week, Stephanie and Luis decided to see how fast they could sprint 300 meters. They asked their friend Nadia to time them with a stopwatch. Stephanie sprinted first and ran 300 meters in 89.74 seconds. When it was Luis's turn, he sped off and completed the run in 42.1 seconds. How much faster was Luis than Stephanie in seconds?
Solution: To find how much faster Luis was than Stephanie, we need to find the difference between their times in seconds. Stephanie's time - Luis's time = difference in times. ${8}$ ${9}$ ${7}$ ${4}$ ${4}$ ${2}$ ${1}$ ${0}$ ${-\vphantom{0}}$ ${4}$ ${6}$ ${7}$ ${4}$ Luis was 47.64 seconds faster than Stephanie.